Studies on Seasonal Incidence and Management of Top Borer, Scirpophaga Excerptalis (Walker) in Sugarcane

Abstract

Present investigation entitled "Studies on seasonal incidence and management of top borer, Scipophaga excerptalis (Walker) in sugarcane" was conducted during kharif season 2023 at Crop research centre Chirodi, Sardar Vallabhbhai Patel University of Agriculture and Technology, Meerut - 250110 (U.P.), India. Attempts were made to study the pest of sugarcane top borer, S. excerptalis on various aspects such as relation to weather factors for seasonal incidence population build up and management strategies. Moth trapped in the pheromone trap of sugarcane top borer, S. excerptalis firstly observed in the first week of May (18th SMW at the mean temperature 23.6 °C and RH 68.2 per cent) with minimum mean population of 2.0 moths per trap/week and 18 moths per traps in July, the mean temperature 30.05 °C and RH 79.20 per cent. Leaf infestation of sugarcane top borer, S. excerptalis (0.27 Leaf infestation per cent) was first time observed during mid month of May (19th SMW at the mean temperature 28.55 °C and RH 39.55 per cent). Dead heart of sugarcane top borer, S. excerptalis infestation of sugarcane was minimum 0.47 and maximum 14.68 per cent showed fluctuating trends during the entire crop period and reached to its maximum level in August at the mean temperature 30.60 and RH 78.55 per cent during the year 2023. Bunchy top of sugarcane top borer, S. excerptalis was found 0.47 per cent/week in the 25th SMW at the mean temperature 31.50 °C and RH 67.95 per cent) and maximum Bunchy top of sugarcane 17.28 per cent/week in the 34th SMW at the mean temperature 29.30 °C and RH 84.45 per cent). The correlation of top borer was found highly significant positive correlation with minimum temperature (r= +0.820), maximum (r= +0.723) and minimum (r= +0.763) relative humidity and rainfall (r= +0.511) along with negative correlation with maximum temperature (r= -0.214). Efficacy of different treatments on incidence of top borer, S. excerptalis among all the treatments showed significant effect in minimizing the top borer incidence as compared to untreated control. The treatment Chlorantraniliprole 18.5 SC @ 375 ml/ha was found best with minimum incidence of 4.00 per cent in the year 2023. The maximum cane yield of 89.00 t/ha was recorded in the plots treated with chlorantraniliprole 18.5 SC @ 375 ml/ha and minimum cane yield was found in untreated plot with 58.00 t/ha. The maximum incremental cost benefit ratio 1:9.54 was recorded in treatment chlorantraniliprole 18.5 SC @ 375 ml/ha and minimum 1:2.04 was found in the treatment Spinosad 45 SC @ 225 ml/ha.